C1569 Wine must Have a Bitter Taste!

Article 1569. Wine must have a bitter taste!

Does this mean that he is still some distance away from Tree Chopping Elder's request?

He had already tasted the sweetness of the wine and the mellow fragrance of the wine. What else did he need to taste?

He had gone from being indifferent and tasteless to this step, step by step, and had yet to succeed?

Then what was still lacking?

"Bitter taste